Breathing mask



FIG. 1 is a perspective view from above and one side;

FIG. 2 is a view of said one side;

FIG. 3 is a view of the opposite side;

FIG. 4 is a front view;

FIG. 5 is a rear view;

FIG. 6 is a top view; and,

FIG. 7 is an underside view.

The ornamental design for a breathing mask, as shown and described.